A family friend has asked your help in analyzing the operations of three anonymous companies operating in the same service sector industry. Supply the missing data in the table below: $($Loss amounts should be indicated by a minus sign. Do not round your intermediate calculations.$)$

$\backslash$table$[[$Sales$,$Company A$,$Company B$,$Company C$],[$$$,420,000,,$$$,,50,000,,$$$,650,000,],[$Net operating income,,,,$$,,35,000,,,,],[$Average operating assets,$$,151,000,,,,,,$$$,153,000,],[$Return on investment $($ROI$),,17,\%,,-,18,\%,,-,\%$